Dr. Gina Poe: The Science of Better Sleep

Transcript from https://podmenti.com/t/e82a0a41e354a2fa

I think it's actually a good sign to not remember you, Dream.
To me, it means that your whole brain was asleep and doing what it should be doing, which is not recording new memories.
But rather processing old memories.
Don't worry about it.
Maybe it's a bummer that you don't remember these crazy dreams that other people come up with and seem so entertaining.
But it's actually probably a really good sign that you're
Sleep is efficient and healthy.
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Today my guest is Gina Poe, PhD, a professor in the Department of Integrative Biology and Physiology at UCLA.
We discussed sleep, which is her area of research, specifically how it impacts emotions, memory, learning, and more.
We also dive into what sleep is, the phases of sleep, dreams.
and the effect of routine on sleep and cognitive performance.
This episode is full of practical science based information you can use to improve your sleep tonight.
It's time to listen.
and learn.
Uh-huh.
Let's start by diving in and talking about sleep, which is sort of the focus
of this episode.
I guess I wanna start with what is sleep and what is it for? Which sounds like a very simple question, but I don't know if we're gonna get a
If it's that simple.
It's for a lot of things and that's what's great about it. Uh it's not a waste of time. Your brain is really active while you're asleep.
And uh we know a lot about the functions of sleep right now. Uh, whereas even thirty years ago
We
Basically had very little idea.
Um, or actually rather lots of ideas, but very little hard evidence that it was for anything in particular.
We know we can't do without it.
That's the first thing. Um animals that don't get it. For example, there's a
biological condition called phatofamilial insomnia and that's where people develop a
an inability to fall asleep and unfortunately it's fatal after a few months.
As you can imagine, they don't develop this. This is it's a genetic problem and people don't develop this until
after child bearing years and so
Um that's how it is.
The case that
one family and a couple of families in particular have been able to pass this along.
But that's helped us to realize that sleep is absolutely essential for life.
And so what do people die of when they don't get enough sleep? Well, it's um unclear because it seems to affect
Multiple organ systems affects our brains.
our metabolism
our skin um our immune system
Just a lot of things and so what people die of are various things depending on what it targets first in them.
Or what it uh tar uh targets.
worst in them.
But in terms of getting sleep, it's for a lot of great things. Um all those things I just mentioned.
It's good for our immune systems and all of our organs, including our brain.
And what it helps in our brain is it helps us to
resolve emotions to learn better
And to actually just clean our brain and restore
the energy balance in our brain so that we can function well the next day.
How would you define sleep? I want to go into sort of um
resolving our emotions and cleaning our brain. But before we do that, how would you define it? Uh so
Uh sleep is behaviorally defined as an inattentive state, uh where we're less attentive to the world around us.
It's reversible though, so we can definitely wake ourselves up unlike coma.
And um we usually have a characteristic posture and um
And it's homeostatically regulated. So if we don't get enough of it
I
Our brains, our bodies will demand more.
of it.
To make up for them.
Sleep that we've lost.
We've recently discovered in the last few
Five, six years.
That
Sleep isn't necessarily a whole brain at the same time phenomenon.
That in fact some of our
brain can be asleep while other parts of our brain can be awake.
And that's probably what sleepwalking is about.
We are unconscious, but we are awake enough to be able to
interact with the world around us. In nature, because we we sort of had to be on the alert for predators and prey even while we're sleeping and resting? It could be. Um
It's actually just as difficult to awaken a sleepwalker.
than it is someone who's fully. So
I don't think if it would be evolutionarily
you know, um demanded. However
There are creatures, not humans, that can sleep one hemisphere at a time.
Where one hemisphere is awake and uh has the eye the eye that
uh is governed by that hemisphere is open.
and actually alert to the world around you.
And the the other eye is closed in the hemisphere that
Governs that I
is asleep.
So um it's actually just fully awake and fully asleep.
Uh someone asked once whether we could do that, and there is no evidence that we can.
But certainly
parts of our brain can be asleep while other parts are awake.
And that
seems to be you know a not adaptive situation. That's when
We have micro sleeps, for example, and
uh we could miss things when we're when our brain is asleep.
parts of our brain that are asleep, including you unihemispheric sleep.
Sleeping animals.
is really asleep and
Part of that is being inattentive to the world around us.
We really need
To be closed to the world around us.
In order for sleep to do its thing.
And and speaking of doing its thing, one of the things that you mentioned was resolving emotions and cleaning out our brain. Can can you dive into those a little bit? So both of those have been long suspected to be functions of sleep, but only recently have we evidence that this is the case.
We all feel
Like our brain is full and gunked up when we're sleepy and we need to get to sleep.
But it's only been
In the past ten years or so.
We realized that
There are actual the slow waves that we
Didn't know what their function was.
When we fall asleep.
are actually sweeping through and cleaning our brains from the debris that builds up
across wakefulness.
Proteins get misfolded.
as they get used and
Um we need to refold them. We also need to clear away the debris of metabolism.
that happens through these slow waves sweeping through almost like a bilge pump, I think of it, like a bilge pump, pumping out the waste.
Um, as far as emotional
mem um learning we all realize that if we don't get enough sleep
We get cranky.
And it's even more true of children who are developing if they don't get their nap or don't get enough sleep, they get
Really hard to manage.
But it's only been recently in the past ten years or so that we've
been able to see how that happens and
mechanistically what is actually happening to our emotions.
We still only have a lot of hypotheses and
possible mechanisms that should work now.
So we still it's hard to study emotional system.
Especially in animals that can't talk to us.
Um we can see evidence of volatile emotions, but
It's hard to get
Um
Mechanistic studies because animals
have a difficult time telling us how they're feeling, um, unlike humans and
It's
Fairly um
problematic to deprive people of sleep too much, especially children where it's so obvious.
We definitely don't want to deprive them of sleep because
um sleep is really important also for a lot of developmental steps that
have critical time windows, and if you lose that
Sleep in that time window.
you lose the opportunity to fulf that part of the brain.
And we're sort of talking about this as if this is a constant process happening throughout the night, but are there are different states of sleep or different things happen at different points of time in our sleep.
Yeah, there are three
kind of gross states of sleep, but um people have characterized as many seven sub states of sleep that um
happened throughout the night.
Uh, typically we have about a ninety minute cycle. On average, it's about ninety minutes.
where we go through all the stages of sleep and they start with
First the drowsiness.
Which is kind of stage one.
We were being less attentive to the world and
We start to have amnesia if someone's talking to us.
while we're in this stage one of sleep, we might be able to
hold a conversation but we won't remember it. We could read a page if we're reading a book.
But we won't remember what was what was said on that page.
Then we go into a deeper stage, which is stage two.
And that is where we start to get sleep spindles, which are these
fifteen, ten to fifteen hertz.
blips in our brains that um

parts of our brains at different times.
And these things called K complexes, which are big surges of activity in our brain.
And that's when we are definitely fulcious, but if you wake up someone out of that state
Or they spontaneously awake out of that state, they will say that they have had
Hallucinations, kind of like dreams, but not full dreams. They're like they're called
Hypnagogic.
hallucinations if no being sleep. You know, that's where some of these hallucinations are quite
Vid and scary sometimes.
So waking up after just falling asleep after about five minutes.
you can have sometimes what our report is as kind of a scary dream that's not a full fledged
Dream but
Almost like uh
Just a perceptual hallucination.
Then if we successfully
go to the next stage of sleep. That's our deep slow wave sleep where
Um, there's a slowing of our rhythms in our brain.
And there's a
periods of silence that last about a hundred milliseconds or so
And then periods of high activity, but it's all synchronous.
um throughout our brain.
And that's
Synchrony is almost like white noise. You know, it's just
Everything active at the same time, everything silent at the same time.
it um interrupts the communication that would happen between the different areas of our brain. So that's a deeply unconscious state of the brain, but it's also a state where if there are portions of your brain
That are awake.
you could do things like sleepwalking.
Sleep talking.
sleep baking, sleep driving. It's uh it's pretty dangerous in the sense that you don't really know what you're doing and you're not
There have been cases, legal cases, where people have been acquitted out of a crime because
Um it could be shown pretty clearly that they were asleep at the time.
After that we
Transition back to the N Two stage of sleep.
And that
transition on the way to rapid eye movement sleep, which is the dream state.
is called the transition to Rem sleep.
And that's where really interesting things start happening. We start having
more uh vivid dreams but have a little more content to it.
But it's not until we transition to full fledged REM sleep.
That we have our full fledged long
involved crazy dreams. Um
But in that empty state again we have those sleep spindles.
And those K complexes, and those seem to be really important for.
Helping to consolidate our memories and update our schema.
With the things that we learned the day before.
Yeah, it's it's just a very plastic time in our brain, uh and it's
really kind of the opposite stage of wakefulness in the sense that
all of the neurotransmitters that are high when we're involved in
Uh
Interacting with our world.
Are low
and neurotransmitters being the neurochemicals in our brain are really low during that N two transition to REM.
And our thalamus, which is our gateway to consciousness, it's where all the outside information
gets sorted and put into various parts of our
cortex so we can respond normally and rationally to it.
it's completely closed. That thalamic gate is closed during that into transition to rim.
So it's actually in in some sense the deepest stage of sleep we are
Least
awake in that state. And then we go into REM sleep, which is
Actually paradoxical because it
And it often it's called paradoxical sleep because
Our cortex looks like we're awake.
our cortex looks like it's responding to the world around us, only it's not.
Because our thalamic gate is still closed.
And instead our cortex is responding to internally generated
Q. So
Instead of excitation coming from the outside world, excitation is driven inside.
And it's thought to be random and that's maybe the source of the randomness of our dreams, but in fact
It may not be random at all. It might be quite directed.
Sure them.
the functions of that rim sleep.
dream is trying to accomplish.
Oh man, I have so many questions. We're gonna go a bit all over the place here. But one of the things he said is like if you wake up right away after you go to sleep.
Uh somet I I know that happens to quite a few people actually. They fall asleep, no problem.
And then sometimes they'll wake up sort of like five to eight minutes later and then they can't go back to sleep.
That's really interesting. Well, it might be
If you have a really efficient
And two stage sleep.
You might be able to accomplish some of the functions of that.
Of sleep.
Including some of the
Energy packets ATP
that get depleted across wakefulness.
And so
I wouldn't worry about not being able to go back to sleep because in fact
I think some of that
function of sleep has already been accomplished and that's and that's good.
Um, even some of the memory functions of sleep and um
Creativity functions asleep could have been
um accomplished even in that short period of time.
However
The deep cleaning portion of sleep cannot happen within that period of time.
nor the refined kind of remodeling uh of RAM sleep could happen. So
Don't think you can just get away with eight minutes of sleep and be fine for the next day. No. Um in fact you do need still to clean your brain.
And to
Do some
refined work and um emotional work.
of Ram sleep. So
Don't worry, uh but also
Don't give up. Don't give up on getting up all night.
Sho should we get out of bed if that's the case? Like I I think it's normal for most people to wake up at least once during the night, whether they're even conscious of it or not, whether they go pee or or sort of like some people
uh often wake up at like two or three AM and and can't go back to sleep for a little bit.
Is w what should people do when that happens? Should uh not beat themselves up, I guess, but like
Definitely don't beat yourself up or get anxious about it'cause anxiety will
Inhibits your ability to go back to sleep.
Trust your body.
And if your body's saying, Hey, I really need to get
This one thing done.
before I go back to sleep, I'm not gonna feel good unless I get this one thing done.
Get up and do it.
You know, just do it and then
Uh and then go back to sleep. You'll feel better.
You'll feel better or less anxious.
And that will help you go back to sleep. Um
If you're lying there worrying and there's nothing that can be done about it, you know, this or at least not d done at that time, if it actually requires you to go into the
into work to do this thing that you're worrying about or um
call someone and it's the middle of the night and you can't talk to them, um
Instead
Try and you know, write a list.
To help yourself.
feel more ready for the next
To accomplish that thing the next day.
Or, you know, meditate, deep breathe, try and put yourself back into
A place where you are happy and relaxed.
And some people, you know, I mean maybe it just
requires distraction.
Maybe playing a
mindless uh video game um on your phone with your blue light off. You need to turn down that blue light because that's a
Circadian clock resetting signal that you don't want.
I I play threes on my phone. I don't know if you've ever seen threes.
You know, it's like you put blocks together to form three and then you put threes together to form six, and you know, if there's no high stakes in it, it's
It's just enough to occupy my mind, so I'm not thinking about uh other things, but
It's not
um exciting enough to keep you awake.
And I just
fall asleep beautifully on that. Yeah.
So one of the things you said led me to believe that we sort of dream every night. Everybody dreams every night. Yeah. So why is it?
Some people can remember their dreams and some people like me
Rarely.
remember what they're dreaming.
Yeah, I think it's actually a good sign to not remember your dream.
To me, it means that your whole brain was asleep and doing what it should be doing, which is not recording new memories.
But rather um processing old memories.
Don't worry about it.
Maybe it's a bummer that you don't remember these crazy dreams that other people come up with and seem so entertaining. Um, but it's actually probably a really good sign that you're
Sleep is efficient and healthy.
But for those who remember their dreams all the time also I'd say don't worry about it.
Because um
What it what it
probably means and we don't really know the answer to this again because we can't ask animals to recount their dreams to us.
But what it probably means, and this is something that we just discovered.
six years ago in animals
And just last year we published it in humans.
There are it's
possible that the hippocampus which is your new memory
Writing structure, kinda like your
You know, like a thumb drive.
is normally
very it's not very well connected to the rest of your brain.
During Rem sleep.
But it might be that it's better connected in people who remember their dreams and it's functioning to
Record those dreams.
Such that you remember them when you wake up.
So is it good or bad that the hippocampus is better or worse connected with the rest of your brain?
We don't know the answer to that. We don't know the answer to that at all. So
Um that's that remains to be seen. You mentioned sort of kids and sleeping.
and brain development. So I think our brains develop to where, you know, twenty two to twenty five ish. They're still developing. Yes. So a as a parent of two teenagers.
What what does this mean for me as a parent? Do I wake them up on the weekend? Do I let them sleep until two PM? How how do I what do I do here to encourage brain development? I don't know. My mom used to wake me up at like seven o'clock with a vacuum cleaner.
I love that. Um
My husband is a is a physician and people would come to him with that question. Um
And really it's not a problem with the teenager. The teenager can sleep fine and and should sleep. Um, we need they need that sleep too for that brain development.
Um it's a problem with parents that we don't like it when our teenagers sleep in so late. Um it it makes and it it's a problem with school schedules too.
Um schools are not set up to allow teenagers
to both listen to their own biological rhythm which tells them
Um
via combination of signals, um
Yeah.
Yeah.
Children have a very strong circadian clock and
It helps them wake up in the morning, it also helps them
Go to sleep nicely at night.
Um te teenagers have a circadian clock, of course, and it's much better than the circadian clock of older people, but
They have all
Um many other things that their brain and bodies are attending to besides that clock.
Which tends to push their bedtimes to later.
Yet they need just as much sleep.
as a twelve year old because of all the brain development that's still going on. So
So that
combination of
later bedtime and needing enough sleep.
and not having a circadian clock that's quite as strong as a child's.
allows them to sleep in and get the sleep that they need.
They also need more REM sleep. There's a lot of emotional and processing, and that happens mostly during that REM sleep stage.
So um teenagers who are able to get an extra hour of sleep every night
are usually able to better
Cope with the world around them.
including their parents. So they're less emotionally labile, they're happier.
Less depressed, less anxious.
Um better able to cope with the social uh pressures of school.
I say if it were me, let them sleep, um
But my husband, um, you know, as a physician, you know, helping parents
treat their teenagers
And also Cicadian Rhythms person himself.
um says, you know, wake them up. So I think either way, as long as they're able to get to sleep.
At a decent time at night.
Is is is better. And
One of the things that
allows a teenager to get to sleep earlier than later.
is to not have all the electronics and the Facebook and whatever it is that
keeping them engaged really actively engaged um
make it boring for them at night if possible. Um, so that they less have less
social emotional um reasons to stay up.
And that part of that is also for the parents to go to sleep.
at an early time. Make it but
Parents being awake um till midnight.
Uh it's hard for a teenager
Who has so very attuned to the world around them.
to be able to go to sleep when stuff is happening in the house.
You know, so um
For teen for parents to make it boring enough that teenagers could
Good.
um fall asleep at a decent hour.
It sounds like new electronics maybe in the bedroom if you can get away with that as a parent might be a good uh sort of Oh, absolutely. And
It's been sp shown in study after study.
that teenagers that have electronics far from them
Outside the room.
have much better um social emotional
uh performance.
W what have you seen work there? What's effective? Like leave your device in the kitchen or what do you leave your device in the kitchen charging on a put the only chargers available in the house outside your bedroom.
Yeah.
And then talk to me about the importance of sort of like
routine and timing of sleep. Like how important is the
two to three hours leading up to sleep, and then sort of like the consistency around times we go to bed and how that impacts us.
Yeah.
have been studies to show that the more volatile your sleep
P onset time.
the worse the cognitive outcomes for older people. So
It hasn't really been studied as much in younger people.
But if you have a regular bedtime in older people you're
uh it's predictive of better cognitive outcomes.
Two things control our sleep. Our homeostatic need, which is the longer you're awake, the more you need sleep.
And the other is the circadian clock timing of it.
So um one thing that helps you
to have a good, solid, even circadian clock is in the morning when you wake up.
Expose yourself to bright light because bright light
Um, especially in the blue frequency.
is the strongest resetter of our daily clock.
And that starts the clock.
at the right time of day so that you're ready to go to sleep.
At night.
Sacadian clock.
Is
One of the things that
its drive for wakefulness starts relaxing at night.
At the same time that the homeostatic need for sleep builds.
And so that allows you to go to sleep at the right time. If you expose yourself
to really bright light in the evening, for example, with a electronic device with lots of blue.
in the frequency of light
You are setting your clock
to h to say, Oh, it's time to wake up.
And so then your homeostatic
Need for sleep.
And your circadian rhythm are fighting one another.
Yeah, so there are lots of things that such your circadian clocky sides like.
Timing of meals.
Um timing exercise.
All of that can um
And help you
Know what time it is, so you know what time to go to sleep. It is to go to sleep.
jet lag is a problem because
You need to reset that clock and
Our clocks can
They shift by about an hour a day.
So
If you're flying six hours uh time difference.
It's gonna take you a few days to um really reset to that new
Uh.
Now in terms of what you should do before you go to bed to maximize your
uh ability to go to sleep.
So you have also sort of uh your autonomic nervous system, which is
Fight or flight, which is a sympathetic nervous system.
Or rest and digest is a an easy way to say your autonomic um
Very sympathetic system.
The parasympathetic system dominates as it should during sleep, rest and digest, right?
Um
That does not mean you should eat a big meal before sleep, by the way. Um But anyway, the Adonom parasympathetic system um dominates.
And so anything that riles up your sympathetic nervous system, the opposite one, is not something you want to be doing right before bedtime.
Well w what does before bedtime mean, though? Is that like the preceding thirty minutes, ninety minutes, two hours? Like is there a time ascribed to that?
I think that varies by individual.
For example, I know some people who take a very cold bath.
Um and then
then they take a hot shower just to warm up so they're not freezing anymore.
And then they get into bed. And what that cold bath does is it actually
activates your sympathetic nervous system. You're very aroused. You're very alert and awake during that cold bath.
But almost
Works like a
Reset.
Of your
sympathetic systems like a big
Button push.
that allows a parasympathetic rebound when that stressor is over.
So within thirty minutes
you know, they once they've warmed up a little bit, they feel so much
more able
to get a good night's rest and there's some evidence that
the sleep that they get is really, you know, good sleep.
For me that doesn't work. It's so stressful to me that I just, you know, it I I it takes me too long.
To relax after that. Okay. But a warm bath is perfect, you know, because that's
helping the parasympathetic system.
do what it does. So um
And it sounds like consistency is sort of key, right? So you're also like every it it it sounds and correct me if I'm wrong here, like everything you're doing.
during the day is telling yourself what time of day it is. So you're you're influencing your sort of circadian uh clock in your head, whether you have coffee or whether you're eating late or playing video games or whatever you're doing, you're sort of like sending it signals.
And so it sounds like consistency is sort of the key. And also if you are consistent.
I'm assuming it it also talks to your subconscious about, oh, it's a bath. That means we're like cueing our bedtime wind down routine and Yeah, we are creatures of habit. And it might not just be our conscious mind, but the rest of our body that's also paying attention.
to that habit.
And helping us wind down and get sleep.
So yes. And that plays into the time thing too, right? Like sort of like trying to eat around the same window and trying to go to bed around the same window. Yes, exactly. Exactly.
Uh, I wanna talk about exposing yourself to light, which was you you mentioned
at this the start of that answer, sort of like light exposure first thing in the morning is super important.
Should we have blackout blinds in our bedroom ideally, or is that uh well, during the summer time, if you're in a northern hemisphere, um
Or I guess no matter where you are during the summertime.
The days are l light longer.
It's possible that you a blackout blind would help you fall asleep.
Better.
At night.
Um, but in the morning you definitely don't want that blackout blind. You wanna open those shades and expose yourself to as much light as possible.
Well, first thing, right, when you wake up.
Like do you w do you wanna is it ideal for people to sleep in a room with a blackout blind, I guess, is say and then open it when you first wake up, but You know, I suppose if you are in a bright city, you live in a bright city with lots of
street lamps that shine directly into your window, then sure, yeah, it'd probably be good to have blackout lines.
Where I live it's dark enough that
You know, I don't need it. And in fact I like to have it
My windows open or the shades open just because that wakes me up in the morning with morning light better.
Totally. And what what sort of things can we do to make our sleep more efficient and maybe encourage more RE sleep?'Cause you you seem to think that that was uh part of the most valuable parts of sleep.
You know, actually one of the things that we don't know yet is whether
Quantity is
Yeah.
is equivalent to quality, right? Um and
So more is not necessarily better. In fact there are some sleep disorders where
People have hypersomnia, uh hypersomnulence.
or too much rem or rem too early.
uh in the night. So it's also the timing
relationship between the sleep states.
That seems to be important.
Um
If you are learning something um or have a an emotional day that you will get more REM sleep. It's homeostatic. It's automatic. You don't need to worry about it.
Um, you'll get it. Your body will get it if it needs it.
And um
So if you're learning a lot.
And you need more room sleep to consolidate that.
it will get more REM sleep at the cost of other states of sleep.
Uh if you can just sleep longer, then those other states of sleep don't have to suffer.
Um in addition to it.
In the first half of the night
you get more of that deep slow wave
you know, uh cleaning sleep.
And in the second half of the night, uh toward the wee hours of the morning
you get more REM sleep. So I said on average
You go through all those states of sleep within ninety minutes.
But in fact, in the first half of the night
more of that ninety minutes is spent in
deep slow wave sleep and less in REM sleep.
And in the second half of that night, more of that ninety minutes is spent in Rem sleep.
unless in deep slow wave sleep. So
If you go to bed too late, you will actually miss the window for that deep slow brain cleaning sleep.
Um, and the sleep each you'll get is more REM sleep.
If you wake up too early.
Um, you go to bed at normal time but wake up too early, you'll be missing a lot of your REM sleep.
So um
You might be fine in terms of brain cleaning, that you will not have done all the
memory consolidation and emotional
um resolution stuff.
That that that's fascinating. So we don't just catch up if we like go to bed later, we sort of like miss our window.
'Cause it's almost like programmatically our brain starts to
to do a function at a certain time and if we're not
asleep at that time, we're not getting it, even if we shift our time. Right.
But don't fear, don't worry if you miss a night's
Sleep.
Or one night you
Just can't get to bed at the regular time.
And the next mor the next night you will probably be sleepier earlier.
And if you can go to sleep a little bit earlier.
You will
Catch up on that deep slow wave sleep that you missed the night before.
And also the slow waves become
Um bigger.
and more efficient. And so
So your brain will will do its best to make up for that lost sleep.
It'll adjust knowing that you didn't get some last night, and so we need to get extra tonight. That's fascinating.
There are limits, um
Yeah, y there are limits to that.
homeostatic ability to adjust, um, unfortunately.
We can't just not sleep for a week and then
sleep regularly the next week and just have more efficient sleep and make up for it. That's not the way it works. You will actually
Suffer.
And one of the things that suffers and we don't know how it adjusts is our immune system.
Um that's something that gets
Is able to also learn through sleep. For example, if you get a
A vaccine, um
One day and then
um, go partying that night and, you know, drink a lot of alcohol.
Get to sleep late.
And then that sleep is also influenced by that alcohol, so you don't get all the stages and all the
quality of sleep.
That immun immunization
Will be
Um
At least fifty percent.
Uh less effective.
than it would otherwise be.
Um, and you can't make the up for that by just getting more sleep the next night.
There's a window of time you need to get that sleep.
For that immune that vaccination to
have its effect.
There's a couple of rabbit holes I wanna explore there. One one of which is what what else do we know about the sleep
immunity's uh response connection.
There's a couple of great researchers. Um, Mark Opp is one of them.
He's at the University of
Colorado Boulder.
And um Jim
Kruger, he was he's at Washington State University.
They've done a lot of really good studies to show
that our immune system is definitely compromised.
The first thing that happens with no sleep
On one night.
Is our um natural killer cells
Um get upregulated. So
because it's a highly stressful situation to if for our bodies not to get a night's sleep.
And so our immune system goes on high alert.
And um says what's going on, you know, what what do we need to pay attention to?
And so that's good. That helps protect us from any kind of acute insults that day.
But it also um
Makes us unable
to learn from those things. So the learn from whatever immune challenges
That you had during that day.
And if you're exposed to
Um a virus, for example.
You um
And
aren't as able to rally your soldiers, your immune soldiers to fight that virus.
you will not be able to generate the specific
um soldiers for to fight that specific virus. And so
And so you'll probably get sick.
Why do we sleep more when we're sick or tend to? Yeah, so there is
Um some good studies to show that the immune response
Actually
signals our brain that we need more sleep. So
And I and it's kind of unknown exactly what's going on and why.
Your body needs more sleep, but
If you deprive
someone of sleep at the time that they are fighting an infection.
They will not get better.
nearly as quickly.
So in fact it's actually super problematic in a hospital.
When someone's there for uh
a viral or bacterial illness, something the immune system would need to fight.
And the hospital procedures
Um then
beeping sounds, uh
checks on you, the blood pressure checks, et cetera.
keep you awake or awake awaken you many times and prevent you from getting that deep
Slow wave sleep state. It seems to be slow wave sleep.
That's especially important for the immune system.
If a hospital environment
disallows good quality sleep.
They're actually hurting their patient's chance of getting better.
quickly as quickly as they otherwise could.
Are are there studies on that where where hospitals sort of like take
uh certain hospitals take sleep more seriously for their patients and therefore we could expect them to uh have better outcomes and get out quicker.
There have been hospitals, thankfully, who have um taken sleep more seriously and
only interrupt the patient when it's, you know, critical for their life. I don't know of, and it would be good to get back to you on that one.
of any studies to see whether or not the patients do better.
I would imagine for sure if someone did study it, um, they would find that
To be the case.
One thing that has been studied though
is um whether hospitals take
More seriously.
the sleep of their physicians and nurses and staff.
And if the um schedule of the hospital allows for physicians and nurses
and staff to get good regular sleep.
Then the physicians and nurses
Make
fewer medical errors.
And and that that includes errors in terms of misprescribing something for the patient.
as well as areas that affect their own health like
Needle sticks, um, accidental needle sticks in themselves. Right. Yeah, so the judgment and decision making
the number of accidents go way down if your physician is well slept. So
That might be something if you're have to go to the emergency room, you just ask the physician, hey
How long has it been since you slept? And how much sleep did you get the last time you slept? Um
And then if it's really a bad uh situation, you might want to ask for a second opinion before.
That's fascinating. Reminds me of that young Sheldon episode where he starts asking his doctor where he went to school and what kind of a grades he got. Oh my goodness. Um is there uh d do we know of any link between
nutrition and the quality of our sleep.
And what we eat.
'Cause it seems like the function for everything sort of like
uh often comes down to what we eat.
And sleep.
And I'm wondering if there's a connection between the two of those things.
Yeah, I think um that is a
Br brand new field.
that hasn't we haven't done enough research on it. Um
It was really very recently that we realized that
the enteric nervous system, the you know, our whole gut nervous system.
Um
is as intelligent and um influential in terms of our health.
as our brain is. Um so
It's not a separate nervous system. They're connected.
But they're disconnected enough.
Such that our brain is not really consciously aware
of the same things our gut is aware of. So I think it's a really good question. We do know that our microbiome or biome um
generates neurotransmitters that affect our brain.
And some of those neurotransmitters are really important.
to either be present or absent during sleep.
And so um that
thing that we mentioned earlier, which is having a big meal just before you go to sleep.
Having our whole gut.
work where as normally it should be
Um resting.
uh might also be generating neurotransmitters that shouldn't be there when we're sleeping could make our sleep more less efficient.
Well
Okay, there's some
Conflicting evidence. Okay, once is having a big meal
Makes people have
More nightmares, more disturbing dreams.
That they remember and that probably is because they're
Awakening out of sleep more often.
Um in so in order to have
The consciousness of those
Disturbing dreams and nightmares.
Um but
There have also been studies in babies and in um infant rats that have a warm a belly full of warm milk.
is the best thing for REM sleep. Yeah, so it might be that uh it might have to do with the complexity of the meal that we've had or um
Up close to bedtime.
And whether or not we're an infant.
But
Anyway, infants
it's great for uh a nice belly full of warm milk is great for for sleep.
It might also be oh
Nice belly full of warm milk is good for adults. Um, there hasn't been a good study on that.
Yeah.
That's a a future area.
Yeah.
You you mentioned sort of like the the um
different parts of sleep at different times. Like the first part of sleep is is
doing X and the the latter part of sleep is doing Y with sort of like the the deep rem.
Uh, and the first part is more like the cleansing.
Of your brain.
If you had to miss one of those parts and you were forced to choose, do I go to bed late or do I get up early?
How would you think about that choice?
Well, I'm a night owl myself, so you know, I would like to go to bed late, but in fact if I had to choose rationally, it would be getting up early.
because we do get REM sleep in the first half of the night. And that REM sleep is really important. That REM sleep we get in the first half of the night.
is really important for
Learning and memory as well.
I would say don't don't do either. Get your full night's sleep. Well, I'm just thinking if you if you had to choose for a flight, say, whether you're getting up early in the morning or you're arriving late at night, so one of which you're gonna miss you're gonna miss a certain part of sleep, how would you
sort of like go about making this. I get up early in the morning. Okay. I get up early in the morning, yeah. Um
For one thing, if it's early enough light.
I can actually fall back to sleep and get some
Dream sleeping on the plane, although
The person next to me might
Find me drooling on their shoulder, but
No. You also mentioned sort of like I want to come back to this, which was the consistency of bedtimes with cognitive
outcomes for older adults
Is this something that we can improve if we start making our bedtime consistent and like
Adapt back.
to where we would have been had we always had a consistent bedtime, or is this something that's sort of like accumulating and we can stop the accumulation of it by going to bed more consistently?
So I think the best way if you wanna
start going to bed in a at a consistent earlier time. You feel like oh yeah, I do go to bed too late and I don't get enough sleep because of my work schedule or school schedule.
Whatever it is.
So start with wakefulness. Start with wakefulness and manipulate what you're doing during while you're awake.
Um in the morning, even if you're groggy, you you know, pull the shades open.
Or go outside, take a walk.
um vigorously exer exercise
Vigorous exercise also helps your sleep do more efficient.
Do
Stuff during the day that helps you be tired at night.
at an earlier bedtime. So
You know, whether it's getting up an hour earlier or whatever it is.
So that you can go to bed. Because if you just
If you don't do that and you wake up nine o'clock and say, Oh, I went to bed too late last night, I'm gonna get to bed earlier tomorrow
Um, you won't be able to do that because you haven't built up that homeostatic need because you slept in so late, right?
So you need to wake yourself up early.
suffer through a day of tiredness.
And go to bed earlier that night.
And that it'll help your clock to reset to that earlier time.
Awakefulness.
and an earlier time of sleep.
And and then also bedtime routines, that is something that is um definitely recommended.
What it e whatever it is that helps your
Body.
Blue into the fact that it's bedtime?
Um and it's different routines for different people, but um
You know, we'll find whatever works for you.
And and then hit that beautiful window when
of uh to glide to sleep when you can.
Yeah.
Yeah.
And and how long should it take to fall asleep, ideally?
Someone who's getting enough sleep at night, you know, um
takes about, I think on average, fourteen, fifteen minutes, something like that, to fall asleep.
And again, that time shouldn't be stressful, like oh my gosh, I should be getting sleep. Oh my gosh, I you know I can't believe I'm still awake. But if it's taking you 45 minutes,
That's
too long. That means that you're not
trying to fall asleep in the right window of time.
that you are stressing about something, or maybe that's it just means you've had too much caffeine.
During the day, too late in the day, and that's still working on your brain to keep you
Vent that signal.
That homeostatic drive.
Signal.
From hitting your brain. So
That one of the um
most effective ways to
help people with that kind of insomnia.
that delayed sleep onset insomnia.
is to do what we said earlier, get out of bed.
Do something that relaxes and makes you happy.
And then when you're feeling sleepy again, just
Just hit and don't worry about having lost that forty five minutes.
Because in fact you probably would have been awake.
Yeah.
You know, twiddling your thumbs in bed at that.
period of time worrying about it anyway. So
Get up do something useful and not too
Um exciting.
And um that's called cognitive behavioral therapy for insomnia. That's one of the recommendations of it.
And it seems super effective. I've had some friends do that and they're like, It takes three or four nights and then
It seems to work really well. Uh you you mentioned sort of falling asleep later. What about if you
Uh, instead of forty five minutes or instead of fifteen minutes, it takes you like two minutes to fall asleep. What is that?
Yeah, that's um, you know, good for you. A lot of people feel like it takes me two minutes and it's great. Um, that's wonderful. It's usually a sign that someone's not getting enough sleep, that homeostatic drive.
І супер, супер стран.
Um actually people are
Famously bad at knowing how long it takes them to get to sleep.
Because
Because our memory systems, um, this is a paper we published last year.
Our memory system is the first thing
Usually normally to fall asleep.
So um
you might not actually be fully asleep. You might be just that your memory system has fallen asleep in two minutes.
But in actual actuality if you looked at the whole grain
It looks like it's ten minutes or something like that.
However, if you really are asleep in two minutes, like you you have a
bed partner and they're snoring in two minutes time after their head hits the pillow, it's probably a sign that they're not getting enough sleep.
Yeah.
And also snoring is something to
to be cautious of as well because it could indicate
inefficient sleep of sleep apnea. Um
Which is really, really bad for everything that sleep is good for.
Oh, that's super interesting. Okay.
Um
The question that everybody uh likes to ask, because I think we just don't like the answer, comes back to sort of alcohol and caffeine and their effect on our sleep.
And sort sort of like
the the windows in which
Uh they
don't affect sleep as much if there are windows where they don't. I think the half life of caffeine is like six hours.
I don't know what the half life of alcohol is. Yeah, I don't know what the half life of alcohol is either, but I wouldn't doubt it's six to eight hours, something like that.
So the half life of caffeine it's not a half life of the caffeine molecule itself.
it's the half life of our ability, our enzymes ab ability to break it down. And that varies from person to person.
So for me
It's a half life of more like sixteen hours.
You know, I have a whatever enzymes I have, they're just ineffective. I'm maybe more like a dog. A dog doesn't have good enzymes to break down caffeine either, and that's why it's dangerous for them to eat a lot of chocolate or or to get their, you know, get
Get into something with caffeine in it.
So I think I'm a little more dog like in that respect. So if I have
If I have caffeine afternoon,
I am awake until one, two in the morning, you know, I just cannot my brain is just whirling. Maybe four in the morning, depending on when how much ha caffeine I had.
But there are other people who have a very efficient
caffeine enzyme and they can have a cup of coffee at dinner and still sleep great.
So um I think it really depends on the individual and you need to sort of find whatever is right for you.
Alcohol definitely disturbs your sleep.
it may make you feel like you can fall asleep better and a lot of people self medicate with alcohol before bed, but
In fact
Even though it helps you fall into that
Um
First stage of sleep.
Your sleep is not as
Good or efficient, and it actually inhibits REM sleep as long as it's on board. And interestingly,
the um completion of the metabolism alcohol the metabolism of alcohol
Um
sends an arousing, alerting
message to your brain. So a lot of people if they
They're drunk and they fall asleep.
They will wake up at, you know, three, four in the morning.
And
find it difficult to go back to sleep.
Because that alcohol is burned off.
And that alerting arousing signal has has come in. And I don't know
What that arousing signal is, I haven't looked into it myself, so
Um
That's fascinating because there's like a cohort of people I I know amongst my my friends and and other people who
sort of like wake up at three to four in the morning and then can't go back to sleep. And I'm wondering
to what degree that correlates to having a few glasses of wine or a beer or something the night before.
And your body is metabolizing it. And then that's part of what's uh either waking you up or keeping you up if you naturally wake up to P or very well be that.
Yeah. Uh uh I wanna switch gears a little bit here and and talk about some of the stuff you revealed to me before, which is
Um, you were raised by uh I was struck by this story because you were raised by a single mother, you and your brother.
Who often
Uh wouldn't eat.
To put food on the table for you.
Yeah, yeah, we were we were really poor on welfare and um
Yeah, my mother uh would go without meals sometimes in order to feed my little brother and I. My brother's a year younger than me.
I didn't know that we were poor. She was very protective of us and
Didn't tell us, you know.
That we were in any way disadvantaged.
Um and she would she was really resourceful in helping us to
Find ways to get
the the essence of what we needed.
But one of the things that, you know, we didn't get um is visits to the doctor. We didn't have
um, that it didn't have the Medicaid system available at the time when I was growing up and
Um and so routine visits to the doctor didn't happen for my brother and I and when we got sick
My mother just had to
figure out what to do to treat us herself.
And
So I didn't get, for example, a vision check until kindergarten when the school
Did it themselves.
Um, as part of going to school.
And that's when they realized that, you know, I was legally blind in my left eye. Um, and that's something that
They can treat it was just because of the length of my left
orbit is different than the length of my right. And so I just
Favorite one over the other.
didn't use my brain just didn't take the signal from my left eye. And so
It's called amblyopia, and um so I was essentially
just using one eye to get around the world.
And in order to correct that, they had to put a patch over my good eye.
So and force my brain to start listening to and and seeing what's coming from my my left eye.
And that helped a lot. But I still wear
very uh glasses that have m much more correction than for my left eye than my right.
Um, but my three D vision is probably not perfect.
Because of that.
early developmental deprivation monet the
Monocular deprivation.
So yeah, there are definite costs to poverty, whether you re recognize it or not.
She but my mother was just, you know, amazing at
Helping us to get good education, you know, despite
um the pa the places we were living
with um for poor schools poor neighborhoods and poor schools
And you know, she knew that education was the key to
getting ahead and being able to
Not have your options limited.
in the future. So
If she saw that we weren't getting a good education, she would pull us out of that school and put us into another one, whether it meant
taking a special bus to get there or
you know, other sacrifices to to get us to that other school.
So we went to a lot of different schools when I was growing up.
Uh one time we tried this experimental school that was supposed to be great for, you know, people people who were especially smart because they could
you know, in sixth grade I could take calculus class, uh, you know, if I wanted to.
The problem with that school is that it also
you know, giving children the choice of where to go also gave me the choice to go play with the animals on the farm, which is what I did. So after about three months of that, my mother was like, Okay, forget that. You're not going to any classes or putting you back into public school. So um
That's what I did. But
And we also used the church that we started going to to get some
Some people donated money so we could get to
a private school for some of the years and and get some of the benefit of a private education.
Um, which is you know, more language learning and other things.
Um, so I've benefited both from great public schools and great private schools as I was educated.
ultimately ended up going to Stanford, uh for my undergraduate.
with lots of financial aid and um and then to UCLA which is where I got my PhD.
Y your mother sounds like an incredibly strong woman.
very strong, a lot of common sense. And eventu eventually she was able to get
uh go back to school for herself.
Um once we got old enough and um could be left at home while she went to night school.
And um then when I was in college, she went to college as well.
Got a master's degree in public health and
She was a hospice.
Social worker.
W what would you say is the most important lesson you learned from her that you you still think about all the time today?
What my mother had
Best was common sense.
And just a very
Rational.
even handed approach to the world.
She was not.
a radical in any sense of the word, is she
You know, went to bed it.
A regular time every night. She met
challenges with um
With equanimity.
and um reached out to others when we needed help.
And
She was a fighter though. She's she was strong. She never
Just sat down and
Let the world happen to her.
She got out there and
Especially for kids' sake, she
fought for us and made sure that we got what we needed.
So, you know, what she did best for me, I think, is just
Love me and
used I mean she wasn't
Perfect, she had
Challenges of our own and
Uh, but she didn't let those challenges
Get in the way of raising
Hurricans.
Um, and that really taught me strength.
Um, you you told me before we we started recording that science is way more exciting than it looks on TV. Can you expand on that?
Yeah, oh yeah. I did not think I wanted to be a scientist because I thought that, you know, what I saw on TV was
Um, either the nutty professor where it's someone who's completely socially inept.
Or it was Einstein, it was only for true geniuses, and in fact.
And it was for people who didn't mind being loners and just sitting um with thinking about and
Pipetting alone at a bench. You don't
See pictures of scientists, you see them alone always, right? Um, very rarely see them in groups. And in fact, science is an extremely
social enterprise. We really build off one another's
um findings and
ideas, there's a lot of brainstorming, that's a lot of fun.
Conferences are amazing. I just came back from
a learning and memory conference in Huntington Beach this past week and
just to hear what other people are doing.
you know, generate so many more ideas in your own brain about what you could do next.
hearing about the techniques that they utilize, you know, you can start employing them.
They will come help you utilize them in your own laboratory. You can go help them.
And right now the pace of science is so
mind blowingly fast that
Alm it's almost the case that no matter what experiment you can think of
You can figure out a really good way
to approach it um with the tools that we have now.
and that we can share with each other and the team science. So you might not be able to utilize this tool
But you know someone else who can utilize that tool to help answer.
the question and you do this this other thing and together those two tools
will really be help answer the question.
When it comes to anything, we're only our our hypotheses is uh and our results are sort of only as good as our tools.
abity to measure.
Uh and with the brain and sleep, I mean
You know, it it kind of feels like we're looking at it from a mile away.
And'cause nobody wants to let us like drill into their head while they they sleep, I would imagine. So it'll be it'll be interesting to see how that develops over the next ten or fifteen years. You know, where are we on the right track and where are we totally wrong.
And and on that note, you know
You you have a lot of up and down
uh ideas, right? You you have a hypothesis, you test it, you discover something completely different. I wonder if you can talk to me about some of that journey. Oh yeah, absolutely. That's
really the fun of science. The science
Neuroscies is like building a giant puzzle.
That's um really difficult, but really rewarding. So every paper that we publish is just one piece of that puzzle.
And we don't always know when we come up with a piece.
Where it fits in the bigger picture.
And so we actually sometimes
think that it fits with this other thing. And I don't know if you ever built a puzzle before, but sometimes you think, oh this these two go together and they don't
White fit.
But you think ah, you know, they've gotta fit and you sort of mash it together and it's not until you have more pieces of the puzzle that you realize, oh no
This other piece goes there and that one actually
Still doesn't belong anywhere, but eventually we're gonna find
you know, the use for it. So it's not like
Anything that we come up with if we have rigorous
um approaches to it.
is wrong, it's just we don't always know where things fit. So sometimes
Papers get
Yeah, published.
And not cited and so they you know are considered low impact paper papers because for
Twenty years no one knows what to do with that pa with that.
knowledge.
But the good thing about publications and the record is that they are sitting there and someday someone will say, Well, what about that?
And they'll find that paper and say, Oh, that fits perfectly with this.
portion of the puzzle that I'm building and it so
Um for me personally
The way I've come up with
some discoveries is because I had a hypothesis
That was completely wrong.
Um in fact
Uh so one of them is that I thought that if REM sleep is for remembering
um this memory structure of our hippocampus.
Well
um ac be active in one way during REM sleep.
And if Rem sleep is four
Forgetting like was hypothesized by another researcher
U your hippocampus, this memory structure should be active in an opposite way.
Um, and so I wanted to test this hypothesis. I thought it's gonna be either one or the other. It's possible that REM sleep isn't for memory at all and it's just gonna be all over the place instead.
Um but it's gonna be either one or the other. And the first data set I looked at
was for the forgetting, you know, it had gave me evidence that it's for forgetting. So I wanted to say and before I published it, I said, Okay
Ram sleep is for forgetting, um, because and then I had to look at another data set for another reason.
And I said, Okay, let me see
how these animals um how they how rem how the cells are active during rem sleep in these animals and I found
Quite different. It found it.
it looked like it they were all over the place. So I thought, oh shoot, you know, maybe REM sleep isn't for forgetting because look at the cell animal cells are all over the place.
But when I had to take those cells and
and parse them by whether those cells were forming in new memory.
Or just encoding an old, very well familiar, already consolidated memory.
that the hippocampus wasn't important for anymore.
Um
they fired at opposite phases and the one
That was
The phase at which the familiar already consolidated memory
uh fired was consistent with forgetting
So the hippocampus could be refreshed.
and able to learn.
But the phase at which the cells that are involved in learning something brand new were firing is consistent with REM sleep.
Serving a function for
Remembering and better remembering.
So that's the brain telling me
That my hypothesis was way too simple.
It wasn't one or the other, but in fact the brain somehow knew
Whether it was important to forget this thing because now it's re remembered somewhere else.
Or to remember it because it not has not yet been consolidated.
And that blew me away. I had no idea.
And it took me another
Actually, it's been twenty years that I still don't know the mechanism.
But I have a
brilliant graduate student who's um
now able with the tools that we've got now.
uh Michelle Frazier to actually answer that question that we've had for the last twenty years.
Uh
How it's possible that two cells set uh
located right next to each other but encoding different things can fire at opposite phases.
That's incredible. I I love that journey and sort of like uh
adapting to the data and and
Being open to it.
Um in terms of
You know, I thought this, but now it's this and changing your mind. It
How do you y you approach things with that mentality where it's easy to change your mind?
Well, first of all you have to
Put your ego to bed. Because we're all gonna be wrong if we are striving
And hot on the trail of something that's real.
We have to be open to the fact that we can be wrong and that our hypothesis will always be too simple because
Our brains are complex. That's one thing that everybody agrees on.
And so our hypotheses about how it must work
Um have got to be
Uh
have to embrace that complexity.
Putting our egos to bed is the first thing to do.
Perfect. And sort of the last question I want to ask you is uh what is success to you?
How do you think about that?
A successful life is a happy life is one
Where you can
Brighten the corner where you are, whatever you're doing.
Um
And I might not have been a scientist had I not happened to have a couple of experiences that
showed me that science wasn't as boring as it looked on TV. Um so I'm really glad that I'm able to do science.
But if I had not been a scientist, I'm sure I would have enjoyed my life doing something else, right?
I just like to I think success is to be able to be useful in making the world a better place.
No matter what you're doing.
And for me
the thing that excites me that makes me the happiest probably the most excited the thing that makes me jump up and down
is when I'm able to put two pieces of the puzzle together.
that seem to actually fit and come up with some some answer. I know that
I myself am not gonna be able to do a huge portion.
Of this huge puzzle.
But I'm really glad that I have colleagues that are working on it too.
That are also smart.
I'm also excited.
and can tell me about what they're doing so that we can all
Together.
uh as a community.
solve this really important
thing which is what how our brains work and how we can make them work better.
In cases when they're not working as well.
That's beautiful. I l love that you said uh you know, I believe in this as well, being useful.
I think that's a beautiful way to end this. Thank you so much, Gina.
Thank you, Shane. It's been a pleasure talking with you.
Thanks and learning with us.
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Until next time.